... ,8.8,10.9,12.9 ( General and High strength) >> Surface treatment: plain, black, zinc, electro galvanize, hot dipgalvanization, Dacrotized and ... : 3. Product: Black( M20*140 ) & HDG( M22*130 ) square head screws 4. Factory view figures: PackagingFactory viewTesting equipmentsWorkshop Welcome your visit ...